We begin with a monumental decision by the supreme court. Changes the voting rights act. The law of the land for 48 years. They did it with a declaration. Our country has changed. They were talking about race and the protected right to vote. And this prompted a passionate argument all day long about race in america. And so we begin with abc's supreme court watcher terry moran. Terry? Reporter: Well, diane, this, as you point out, is the biggest civil rights decision from this court in years. It marks the end of an era, at least for now. We have come to register to vote. Reporter: This is why the voters rights act was passed. In some of the darkest days of american history, the act brought hope and action. It transformed american democracy. Today, chief justice john roberts bluntly declared that times have changed, and the law must too. "History did not end in 1965." Roberts wrote in an opinion joined by his four fellow conservatives. The problem, the court held, is that the most powerful parts of the voting rights act targeted only some areas of the country, singling out states an localities that had a proven history of voting discrimination in 1965. The federal fwochlt strictly supervised voting in all those areas. Congress renewed the law in 2006, but basically used the same formula to determine which states and localities should be covered. And that, chief justice roberts declared, was a fatal constitutional flaw. In a dissent, justice ruth bader ginsburg said those that cannot remember the past are condemned to repeat it. Congressman lose, was savagely beaten as a young man. I think what the supreme court did was to put a dagger in the very heart of the voting rights act of 1965. This helped liberate a people and a nation. Reporter: But alan nunnel erk e waumd the decision. We should not be judged on the picture of 60 years ago. I welcome the court recognizing that. . Has changed. Reporter: Will the congress pass a new voting rights act for a new era? Minority voters in parts of the country still face discrimination. It's unlikely such a thing will happen. The change has already come. The attorney general in texas stating that a voter i.D. Law declared discriminatory and illegal under this voting rights act will now go into effect thanks to the supreme court. There's so much argument arouhe country today. Thank you, terry. As you pointed out across the

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